Open Safari (or your preferred browser) and enter: https://secure.timesheets.com/mobile
This will create an icon on your phone, similar to an app. You can rename the icon if you like. Click the icon to access the Timesheets.com mobile site as needed.
Note the instructions for iPad are the same as those of the iPhone shown above with the exception of the location of the browser icon which may appear along the top of the screen instead of the bottom.